.container {
    width: 1000px;
    margin: 0 auto;
}

.banner, .footer {
    height: 100px;
    background: silver;
}

.left {
    float: left;
    height: 300px;
    width: 300px;
    background: burlywood;
}

.right {
    margin-left: 300px;
    height: 300px;
    width: 700px;
    background: darkseagreen;
}

